Covered rollers are used industrially in demanding environments where they are subjected to high loads, prolonged used, stresses and temperatures. They have a diversity of applications, for example, for processing web sheets in paper mills, processing aluminium or steel cans in canning industries, dosage and application of coatings (e.g. paint, varnish), counter pressure for a cutting wheel, to name a few. Due to their application in severe environments, rollers are usually engineered to be large and heavy. They are normally made out of steel or any other suitable metal alloy and in general covered with hard wearing material, such as an elastomer, for example, rubber or a polyurethane material. The covering has a specific function and goal, for example, to protect the roller core. Due to corrosion, temperature differences and other wear-related factor, the outer surface of a roller has a shorter life-span than the average life-span of the complete roller itself. This brings about the necessity of recovering the roller with a new cover, or repair of the covering, for example, by re-grinding the surface. In general, the procedure to re-cover a roller consists of several time consuming steps. The roller is dismantled at the site of use and transported to the premises of a re-coverer. After re-covering, the roller is again transported to the customer and re-installed on a production line. The customer will generally grind the rollers himself in between the different re-covering steps, in view of attuning the covered surface correctly. The procedure for repair also requires the roller to be dismantled from the site of use and transported to a grinding installation usually at the site of use.
The large size and weight of rollers necessitates removal and installation under good Health and Safety practices. This may require the use of lifting machinery, the several employees and hours of lost machine time while a spare roller is installed. The risk assessment associated with such a procedure may also have implications for insurance.
Furthermore, due to the weight and size of the rollers, the cost of transportation is high. The time taken between removing the roller and the return of the re-covered roller (lead time) is high—often several weeks (easily 4 to 6 weeks). Therefore, in order to keep the process running, the operator has to invest in a stock of spare rollers.
The rollers and procedures of the prior art are clearly associated with problems. Roller systems of the art are described in U.S. Pat. No. 6,125,753, U.S. Pat. No. 10,697,805, U.S. Pat. No. 5,601,920.
The present invention aims to overcome the problems of the prior art.